Fastening means for an electrode in a so-called horizontal electrolytic cell



July 15, 1969 P. T. HOLM 3,455,810

' FASTENING MEANS FOR AN ELECTRODE IN A SO-CALLED HORIZONTALELECTROLYTIC CELL Filed Jan. 24, 1966 2 SheetsSheet 1 July 15, 1969 P.T. HOLM 3,455,810

FASTENING MEANS FOR AN ELECTRODE IN A SO-CALLED HORIZONTAL ELECTROLYTICCELL Filed Jan. 24, 1966 2 Sheets-Sheet 2 United States Patent 3,455,810FASTENING MEANS FOR AN ELECTRODE IN A SO-CALLED HORIZONTAL ELECTROLYTICCELL Per Tore Holm, Skoghall, Sweden, assignor to Uddeholms Aktiebolag,Uddeholm, Sweden a company of Sweden Filed Jan. 24, 1966, Ser. No.522,437 Claims priority, application Sweden, Feb. 4, 1965, 1,447 65.Int. Cl. B01k 3/00 US. Cl. 204225 3 Claims ABSTRACT OF THE DISCLOSURE Inan electrolytic cell the electrode is suspended in a vertical rodextending through an opening in the lid of the cell. An elastic sealring is provided to be in contact with the rod and the lid so as toclose the space between the rod and the lid. The rod is suspended insuspension means which support on the elastic seal ring. The resilienceof the seal ring makes it possible to adjust the position of the rodand, consequently, of the electrode.

The invention relates to an electrolytic cell, and more particularly tofastening means for an electrode in a socalled horizontal electrolyticcell, which means a cell in which the active surfaces of the electrodesare horizontally situated. Particularly the invention relates to cellsfor the electrolysis of a sodium chloride solution, in which the upperelectrode, the anode, consists of a graphite plate, and the lowerelectrode, the cathode, consists of mercury flowing on the bottom of thecell. The following specification is concerned with such a mercury cell,but the invention is useful also for other horizontal cells.

In a horizontal cell containing flowing mercury it is important that theanode is situated exactly horizontally, i.e. parallel with the surfaceof the mercury, and exactly on the desired distance from the surface ofthe mercury. This can be achieved by supporting the anode on the bottomof the cell by means of insulating spacers. Such spacers, however,disturb the flow of the mercury and also collect impurities, involving arisk for a short circuit between anode and cathode. Therefore, it ispreferred to suspend the anode in the cell. It is the object of theinvention to provide such suspension means having a simple structure,enabling an uncomplicated adjustment of the anode into the exacthorizontal position, and enabling an uncomplicated raising and loweringof the anode under operation to the desired distance from the mercurysurface. This is essential for obtaining a low electric power. It isparticularly desired to adjust the distance between the electrodes whenusing graphite anodes, as the graphite is gradually consumed. A mediumsize plant for the electrolysis of a sodium chloride solution containsapproximately 15,000 anode plates under operation, and it is thereforeeasily understood that said factors have a large economic importance.

The electrolytic cell of the invention comprises a lower electrodehaving a substantially horizontal upper surface, an upper electrodehaving a substantially horizontal lower surface, an electrode vesselhaving a lid above said upper electrode, a suspension rod extendingthrough an opening in said lid and having its lower end fastened to saidupper electrode, an elastic seal ring to close the space between saidlid and said suspension rod, suspension means engaging said suspensionrod and resiliently supporting on said elastic seal ring, set screws foradjusting the position of said suspension means, against the resilienceof said elastic seal ring, and means in said suspension means forvertically moving said suspension rod.

3,455,810 Patented July 15, 1969 In a preferred embodiment thesuspension means comprise a base resiliently supporting on said elasticseal ring, and above said base a support for a vertical screw-threadedrod the lower end of which carries said suspension rod, said supportcarrying a rotatable nut for raising and lowering said screw-threadedrod.

The invention will now be described with reference to the accompanyingdrawings. FIG. 1 illustrates a vertical cross-section of a device of theinvention. FIG. 2 illustrates the device of FIG. 1 in a perspectiveview. FIG. 3 illustrates an embodiment of the plate of the suspensionmeans, having three screws.

The electrolytic cell illustrated in FIGS. 1 and 2 contains an electrodevessel having a bottom 18, a lid 13, and side walls which are notillustrated. The electrode vessel contains a known graphite anode 1.Alternatively, the anode may consist of titanium or another suitablematerial. The width of the anode is illustrated in the figure, and thelength of the anode is usually three or four times the width. The upperportion of the anode has an opening in which a cylindrical graphite rod2 is fastened by means of screw threads. The rod 2 will be referred tohereinbelow as suspension rod, as it carries the anode 1. The suspensionrod extends vertically through an opening in the lid 13.

A layer of ebonite, for instance, covers the lower side of the lid 13,and extends around the edge of the opening to form an annular member 14which prevents an electric contact between the suspension rod and thelid. The wall 3 of the suspension rod is exactly perpendicular to thebottom surface 4 of the anode. A bolt 5 is screwed into an opening inthe upper portion of the suspension rod. A copper plate 7 is fastenedbetween the head 6 of the bolt and the suspension rod 2, to supplyelectric power to the anode. The copper plate also prevents thesuspension rod from rotating around its axis.

It is desired that the head 6 of the bolt 5 shall be comparativelylarge, so as to press the copper plate 7 hard against the entire uppersurface of the suspension rod 2, for reducing the electric resistance.The electric resistance is further reduced by the fact that part of thecurrent flows from the copper plate 7 through the portions 6 and 5 ofthe bolt and into the suspension rod 2.

A screw-threaded rod 8 is fastened by welding to be co-axial with thebolt 5. Said rod 8 supports a not 9 having a circumferential groove 10engaging the edge of an opening in a supporting arm 11. The ends of thesupporting arm 11 are fastened to a substantially horizontal plate 12.Said plate 12 supports on an O-ring 15 being situated in a recessedportion of the insulating ring 14. The O- ring 15 constitutes seal meansbetween the lid 13 and the rod 2, and the plate 12 constitutes a glandfor said O- ring.

Two bolts 16, see FIG. 2, are fastened to the lid 13 and extend throughopenings in the plate 12. Nuts 17 engage the bolts to press the plate 12downward against the resilience of the O-ring 15. Consequently, theO-ring 15 has the double action of sealing the space between the lid 13and the suspension rod 2 and allowing the plate 12 to be adjusted, bymeans of the nuts 17, into the desired position.

In operation, mercury flows in a thin layer on the bottom 18 of thecell, and is connected as cathode to a direct current source. Thegraphite electrode 1 is the anode. A sodium chloride solution is fed toflow in the space between the anode and the cathode. Chlorine is formedon the anode surface, and the sodium formed on the cathode surfacereacts with the mercury surface.

The anode surface 4 is adjusted to be parallel with the mercury surfacein the following way. A level is placed on the cylindrical wall 3 of thesuspension rod 2, and the nuts 17 are adjusted to make the rod 2absolutely vertical, resulting in the lower anode surface 4 beingabsolutely horizontal. The anode is now lowered by the nut 9 beingrotated, until the anode comes into contact with the mercury on thebottom of the cell. This is checked in a known way by measuring thecurrent or the voltage of the cell. Now the nut 9 is rotated until theanode has been lifted into the desired position.

In the illustrated embodiment both screws 16 with their nuts 17 aresituated in the longitudinal direction of the anode, since theadjustment is most important in this direction. An adjustment in thetransverse direction of the anode can be made if the plate is made withthree adjusting nuts, for instance as illustrated in FIG. 3. A rotationof the nut 17:: effects the longitudinal adjustment, and a rotation ofone of the nuts 17b results in an adjustment in the transversedirection.

What I claim is:

1. An electrolytic cell, comprising a lower electrode having asubstantially horizontal upper surface;

an upper electrode having a substantially horizontal lower surface, saidupper electrode being formed of graphite;

an electrode vessel having a lid above said upper electrode;

a graphite suspension rod extending through an opening in said lid andhaving its lower end fastened to said upper electrode;

an elastic seal ring in contact with said lid and said suspension rodand closing the space between said lid and said suspension rod;

suspension means engaging said suspension rod and resiliently supportedon said elastic ring, said suspension means comprises a base resilientlysupported on said elastic seal ring and, above said base, a support fora vertical screw-threaded rod, said screw-threaded rod carrying at itslower end said suspension rod, said support also carrying a rotatablenut for raising and lowering said screw-threaded rod;

sets crews for adjusting the position of said suspension means againstthe resilience of said elastic seal ring;

means in said suspension means for vertically moving said suspensionrod; and

a flat strip of a conductive metal fastened to the top of said graphitesuspension rod by means of a screw having a head, the lower end of thescrew-threaded rod being fastened to the head of said screw.

2. An electrolytic cell, comprising a lower electrode having asubstantially horizontal upper surface;

an upper surface electrode having a substantially horizontal lowersurface;

an electrode vessel having a lid above said upper electrode;

a suspension rod extending through an opening in said lid and having itslower end fastened to said upper electrode;

an elastic seal ring in contact with said lid and said suspension rodand closing the space between said lid and said suspension rod;

suspension means engaging said suspension rod and resiliently supportedon said elastic seal ring, said suspension means comprising a baseresiliently supported on said elastic seal ring, and above said base 4 asupport for a vertical screw-threaded rod the lower end of which carriessaid suspension rod, said support also carrying a rotatable nut forraising and lowering said screw-threaded rod;

set screws for adjusting the position of said suspension means againstthe resilience of said elastic seal;

means in said suspension means for vertically moving said suspensionrod; and

a flat strip of a conductive metal fastened to the top of saidsuspension rod by means of a screw having a head, the lower end of thescrew-threaded rod being fastened to the head of said screw.

3. An electrolytic cell, comprising a lower electrode having asubstantially horizontal upper surface;

an upper electrode having a substantially horizontal lower surface;

an electrode vessel having a lid above said upper electrode;

a suspension rod extending through an opening in said lid and having itslower end fastened to said upper electrode;

an elastic seal ring in contact with said lid and said suspension rodand closing the space between said lid and said suspension rod;

suspension means engaging said suspension rod and resiliently supportedon said elastic seal ring, said suspension means comprising a baseresiliently supported on said elastic seal ring, and above said base asupport for a vertical screw-threaded rod the lower end of which carriessaid suspension rod, said support also carrying a rotatable nut forraising and lowering said screw-threaded rod;

set screws for adjusting the position of said suspension means againstthe resilience of said elastic seal ring;

means in said suspension means for vertically moving said suspensionrod;

a flat strip of a conductive metal engaging the top of said suspensionrod; and

means on said screw-threaded rod for pressing said fiat strip againstsaid top of said suspension rod.

References Cited UNITED STATES PATENTS 2,542,056 2/1951 Ravenscroft204-286 2,328,665 9/1943 Munson 204-250 2,346,006 4/1944 Burt 33-732,542,989 2/ 1951 Carter et a1. 204-225 2,910,423 10/1959 Schirmer eta1. 204-250 2,919,237 12/1959 Szechtman 204-225 2,986,513 5/ 1961Ornhjelm 204-220 XR 3,037,928 6/1962 Hass et al. 204-250 XR 3,347,76910/1967 Honsberg et a1. 204-288 XR FOREIGN PATENTS 134,612 2/ 1952Sweden.

JOHN H. MACK, Primary Examiner D. R. VALENTINE, Assistant Examiner US.Cl, X.R,

